Evan Sims has official released his first version of a library he's worked up to interface PHP with the GameFly.com video game rental service:

I'm releasing libGameFly, a PHP class for interacting with GameFly.com - the video game rental service. At the moment it's very simple, just allowing you to expose your GameFly queue as a native PHP class and doing... well, whatever the hell you want with it.

It works with some of the feed functionality (RSS/APIs) to grab data about users' accounts. You can download the code here from the project's Google Code page.